Advanced Energy Technologies
Mohammad Rasooli Mavini; Hassan Ali Ozgoli; Sadegh Safari
Abstract
In this study, various configurations design of a Heat Recovery Steam Generator (HRSG) are examined to enhance energy efficiency of a Combined Cycle Power Plant (CCPP). A novel approach is used to investigate ten applicable configurations of a dual pressure Heat Recovery Steam Generator HRSG thoroughly ...
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In this study, various configurations design of a Heat Recovery Steam Generator (HRSG) are examined to enhance energy efficiency of a Combined Cycle Power Plant (CCPP). A novel approach is used to investigate ten applicable configurations of a dual pressure Heat Recovery Steam Generator HRSG thoroughly to explore the best practice models from the energy-conserving considerations. Further, a fuel consumption assessment has been conducted to identify the best performance of the cycle and investigate the minimum pollutants released of each Heat Recovery Steam Generator (HRSG) configuration. The results have revealed that four scenarios among ten, have expressed a considerably better performance regarding; fuel consumption, steam production, energy efficiency, and finally yet importantly environmental considerations. Further, it has been found that in comparison to the conventional configuration, not only the selected scenarios have proved almost four times improvement in the low-pressure steam generation, but also 30% fuel consumption saving in supplementary firing has been achieved which has both economic and environmental benefits. Moreover the carbon dioxide saving potential for the best scenario is 51.37 kgCO2 MWh-1 consequently the environmental benefit of it is calculated about 133,418 $ MWh-1.
Renewable Energy Resources and Technologies
Mohammad Hosseinpour; Hassan Ali Ozgoli; Seyed Alireza Haji Seyed Mirza Hosseini; Amir Hooman Hemmasi; Ramin Mehdipour
Abstract
In this study, the partial alteration of fuel consumption of combined cycle power plants was investigated and analyzed using an innovative model. This system is applicable using the fuel derived from the biomass gasification process. For this purpose, energy modeling of an advanced gasification system ...
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In this study, the partial alteration of fuel consumption of combined cycle power plants was investigated and analyzed using an innovative model. This system is applicable using the fuel derived from the biomass gasification process. For this purpose, energy modeling of an advanced gasification system to supply a share of the gas fuel was fulfilled. The results demonstrated that by considering the reasonable capacities for the design, up to 10 % of natural gas fuel could be replaced with syngas. In addition, heat recovery of the plant stack in the Kalina low-temperature cycle enhanced the total efficiency by up to 1.7 %. Therefore, the competitive advantage of the proposed cycle was enhanced compared to conventional power generation systems. A parametric study of the components affecting the integrated cycle performance including alternative biomass fuels, moisture content of biomass fuel, steam-to-biomass ratio, and equivalence ratio of the gasifier was performed, and the permissible values of each factor were obtained. Thus, by utilizing the proposed approach, it is possible to gradually substitute the consumed fossil fuels of power plants with renewable resources to achieve the objectives of sustainable energy development.
Renewable Energy Resources and Technologies
Saeed Hosseinpour; Seyed Alireza Haji Seyed Mirza Hosseini; Ramin Mehdipour; Amir Hooman Hemmasi; Hassan Ali Ozgoli
Abstract
In this study, an advanced combined power generation cycle was evaluated to obtain sustainable energy with high power and efficiency. This combined cycle includes biomass gasification, the Cascaded Humidified Advanced Turbine (CHAT), and the steam turbine. The fuel consumed by the system is derived from ...
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In this study, an advanced combined power generation cycle was evaluated to obtain sustainable energy with high power and efficiency. This combined cycle includes biomass gasification, the Cascaded Humidified Advanced Turbine (CHAT), and the steam turbine. The fuel consumed by the system is derived from the gas produced in the biomass gasification process. The biomass consumed in this study is wood because of its reasonable supply and availability. The economic analysis conducted in the present research has produced significant gains. The proposed cycle with current prices intended to sell electricity in Iran has a positive Net Present Value (NPV). Therefore, the presented cycle in terms of energy supply has good economic value. Due to the significantly higher purchase/sale price of electricity from renewable power plants in developed countries in Europe or the United States, the power generation cycle proposed in this study may be more economically feasible in other regions than Iran. Of course, with a slight price increase in electricity sales in Iran (3 US₵ kWh-1), the proposed system will have acceptable NPV. Because of the complicated equipment used in high-pressure and low-pressure turbines and compressors sets, the equipment used in this cycle requires a higher initial investment cost than conventional power generation systems. The results showed that the investment cost per unit of energy was approximately 909 USD kW-1.
Advanced Energy Technologies
Sadegh Safari; Hassan Ali Ozgoli
Abstract
In this paper, an electrochemical model was developed to investigate the performance analysis of a Solid Oxide Fuel Cell (SOFC). The curves of voltage, power, efficiency, and the generated heat of cell have been analyzed to accomplish a set of optimal operating conditions. Further, a sensitivity analysis ...
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In this paper, an electrochemical model was developed to investigate the performance analysis of a Solid Oxide Fuel Cell (SOFC). The curves of voltage, power, efficiency, and the generated heat of cell have been analyzed to accomplish a set of optimal operating conditions. Further, a sensitivity analysis of major parameters that have a remarkable impact on the economy of the SOFC and its residential applications has been conducted. The results illustrate that the current density and cell performance temperature have vital effects on the system efficiency, output power and heat generation of cell of the SOFC. The best system efficiency is approached up to 53.34 % while implementing combined heat and power generation might be further improved up to 86 %. The economic evaluation results indicate that parameters such as overall efficiency, natural gas price and additional produced electricity that has prone to be sold to the national power grid, have a significant impact on the SOFC economy. The results indicate the strong reduction in the purchasing cost of the SOFC, i.e. not more than $2500, and improving the electrical efficiency of SOFC, i.e. not less than 42 %, can be the breakeven points of investment on such systems in residential applications. Also, it is found that the target of this SOFC cogeneration system for residential applications in Iran is relying on considerable technological enhancement of the SOFC, as well as life cycle improvement; improvement in governmental policies; and profound development in infrastructures to mitigate legal constraints.
Advanced Energy Technologies
Hassan Ali Ozgoli
Abstract
Fuel cell-based hybrid cycles that include conventional power generators have been created to modify energy performance and output power. In the present paper, integrated biomass gasification (IBG)-molten carbonate fuel cell (MCFC)-gas turbine (GT) and steam turbine (ST) combined power cycle is introduced ...
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Fuel cell-based hybrid cycles that include conventional power generators have been created to modify energy performance and output power. In the present paper, integrated biomass gasification (IBG)-molten carbonate fuel cell (MCFC)-gas turbine (GT) and steam turbine (ST) combined power cycle is introduced as an innovative technique in terms of sustainable energy. In addition, biomass gasification has been explained and shown able to supply the required fuel to the energy generators to compensate for the consumption consequences of fossil fuels. In this system, a molten carbonate fuel cell generates electricity from syngas produced by biomass gasification. In addition, a gas cleaning process prepares adequate treatment before consumption in the fuel cell. Furthermore, for the justification of this system as a combined heat and power (CHP) cycle, a considerable amount of produced heat in the proposed process generates power in GT and ST bottoming cycles. Due to the energy targeting, modeling and simulation of the presented system were fulfilled by the Cycle-Tempo software, and the results showed about 42 MW output power and total efficiency of around 83 %. Further to that, parametric studies represented the durability of the generated power against ambient temperature variations. Finally, changes in total power and efficiency due to the fluctuation of the moisture content of biomass, pressure ratio, and inlet temperature of GT have also been demonstrated.
Hossein Ghadamian; Hassan Ali Ozgoli; Mojtaba Baghban Yousefkhani; Foad Farhani
Abstract
Regenerative Fuel Cell (RFC) systems are used for the enhancement of sustainable energy aspect in conventional fuel cells. In this study, a photovoltaic-electrolyzer-fuel cell integrated cycle has been presented. The proposed system has been designed as a novel approach for alleviating the ...
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Regenerative Fuel Cell (RFC) systems are used for the enhancement of sustainable energy aspect in conventional fuel cells. In this study, a photovoltaic-electrolyzer-fuel cell integrated cycle has been presented. The proposed system has been designed as a novel approach for alleviating the restrictions on energy streams in the RFC systems. Modeling of the system has been performed from the mass and energy point of view, based on both theoretical and practical procedures. To generate electricity from hydrogen, a proton exchange membrane fuel cell, integrated with an electrolyzer system which works by solar energy, has been used. Optimized results of required photovoltaic area have shown significantdifferences between theoretical and practical approaches. Moreover, all efficiencies of two scenarios including total efficiency have been indicated and analyzed. The main advantage of this system in comparison with single solar systems, is generation of internal energy of about 2.3 kW for producing 1 kW electricity by the fuel cell.
